The Fine Dust-Vortex

Fine dust and nitrogen oxides make you sick? This allegation was not proved, writes a group of over one hundred lung specialist doctors in a position paper, and the passion kindled to a jointly controlled debate to driving bans in Germany once again solid.

The doctors, according to a misinterpretation of the scientific data underlying the arguments, the advocates of lead limits and driving bans,.

The world health authority (WHO) and the EU have recently presented Figures showing that around 440,000 people in Europe die in connection with air pollution prematurely.

The Federal environment Agency is also warning in front of 50,000 years of life lost in Germany by nitrogen oxides.

Also, researchers from the Helmholtz centre and the German society for pneumology (DGP) consider it to be proved that nitrogen dioxide are harmful to health.

In this country, so it applies to nitrogen oxides (NO2) , a limit value of 40 micrograms per cubic meter of air, annual average – he is in different cities exceeded. Exceedances of the limit values for fine dust gave it to the Federal environmental Agency, since 2012.

“It is very likely that the scientific data that lead to these seemingly high death, contain a systematic error,” writes the pulmonary specialist Dieter Köhler, formerly Chairman of the DGP, in his Statement, signed by 113 other specialists.

A more important error is, therefore, The common Occurrence of diseases and high fine dust and nitrogen oxide will be described only, but in a causal context. The so-called epidemiological studies, in fact, not allowed, because they serve the purpose. In the result, scientists can set up hypotheses on the causes of and must check with other methods.

In the case of nitrogen oxides is the difficult: Though the substances are corrosive and irritating gases. However, their effects on health are difficult in isolation. Only the observations remain so that people living in regions with high nitrogen oxide concentrations are more common with Asthma, cardiovascular diseases or chronic Bronchitis to the hospital. This is, however, not proved yet that the nitrogen oxides are actually the cause of it.

Fine dust get deep into the respiratory tract

Different is the situation in the case of fine dust: Here is proven,that the small particles, which, depending on the size of the medium-far to very deep in the respiratory tract can enter, the damage to health can. The doubt the Doctors in your Statement, but with different arguments.

Köhler and co. argue: “lung doctors see in their practices and clinics, these deaths from COPD and lung cancer daily; however, Deaths due to fine dust and NOx, even with careful anamnesis, never.” In the case of high mortality, the resulting Figures from the WHO, you would have noticed the phenomenon, therefore, at least as an additional factor in the case of lung diseases somewhere.

Fine dust – what is it?

Fine dust particles smaller than ten microns (PM10), where one micrometer equals one millionth of a Meter. These fine dust particles remain mostly in the upper respiratory tract, i.e. the throat, the trachea or the bronchi. Annual average values of 20 micrograms of fine particulate per cubic meter of air (µg/m3) shall not be exceeded.

Since 2008, the dust grains can be distinguished with a diameter under 2.5 micrometers (PM2. 5). PM2. 5 can reach the pulmonary alveoli. For this purpose, a limit value of 10 µg/m3.

In addition, there is the concept of the ultra-fine particles (UFP, ultrafine particles) that will be discussed in connection with gasoline engines. Are meant still finer granules, which are smaller than 0.1 microns. The ultra-fine particles can pass into the bloodstream and so, in principle, all regions of the body to reach and damage due to inflammatory processes and hardening of the arteries cause.

Basically, dust is created fine everywhere, where the Dirt is stirred up. The vast majority comes from natural sources. Volcanoes blow, for example, large quantities of particles in the air. Also, forest fires and sand from the desert carry dust and fine dust in the air. With time, the particles disperse widely in the atmosphere, so that the load with the distance to the source decreases, depending on the weather.

The Doctors also criticize that different confounding factors such as Smoking, alcohol consumption, physical activity, medical care or taking medication were not taken into account in the studies make sense – even though these have influenced the health.

An example can explain this: It is quite conceivable that people living next to busy streets, can not afford a better living situation. It is also known that people smoke with a low income more often and drink alcohol, worse diet and less to move. What causes lung disease? There are, indeed, fine dust and nitrogen oxides from the traffic? Or maybe the other factors? Or is it all together? To make a simple statement about cause and effect, is not Readily possible.

Meaningful Criticism

Also other scientists have already criticized, that the Figures on premature deaths, as well as the EU uses it to mislead. Because what is actually in advance? A year, a day or a Minute? Instead, one should speak of lost life time. Which, although less striking, closer come, but the reality.

According to its own information, Köhler does not belong to any interest group. He and his colleagues want to serve with the Statement, “the objectification of the discussion”. The aim of the authors was to promote the measures for prevention of Harmful substances. “But you see there is currently no scientific justification for the current limit values for fine dust and NOx.”

Conclusion: Even if the arguments of the Doctors can disprove, for the scientific discourse, the contribution is useful. It belongs to the nature of science, hypotheses, results and interpretations, to doubt, other explanations to offer. This is not to say that the anti-thesis corresponds to the truth. But by the discourse as we approach the reality – the more science can’t provide anyway.